This invention relates generally to detecting diseases of the prostate, as well as to reagents and methods for detecting such disease. More particularly, the present invention relates to reagents such as polynucleotide sequences and the polypeptide sequences encoded thereby, as well as methods which utilize these sequences. The polynucleotide and polypeptide sequences are useful for detecting, diagnosing, staging, monitoring, prognosticating, in vivo imaging, preventing or treating, or determining predisposition to diseases or conditions of the prostate such as benign prostatic hyperplasia and prostate cancer.
Prostate cancer is the most common form of cancer occurring in males in the United States, with projections of 184,500 new cases diagnosed and 39,200 related deaths to occur during 1998 (American Cancer Society). Prostate cancer also has shown the largest increase in incidence as compared to other types of cancer, increasing 142% from 1992 to 1996.
Procedures used for detecting, diagnosing, staging, monitoring, prognosticating, in vivo imaging, preventing or treating, or determining predisposition to diseases or conditions of the prostate such as prostate cancer are of critical importance to the outcome of the patient. For example, patients diagnosed with localized prostate cancer have greater than a 90% five-year survival rate compared to a rate of 25 to 31% for patients diagnosed with distant metastasis. (American Cancer Society statistics). A diagnostic procedure for early detection of prostate cancer should, therefore, specifically detect this disease and be capable of detecting the presence of prostate cancer before symptoms appear.
Such procedures could include immunological assays based upon the appearance of various disease markers in test samples such as blood, plasma, serum, or urine obtained by minimally invasive. These procedures would provide information to aid the physician in managing the patient with disease of the prostate at a low cost to the patient. Markers such as the prostate specific antigen (PSA) exist and are used clinically for screening patients for prostate cancer. Elevated levels of PSA protein in serum can be used as a marker in the early detection of prostate cancer in asymptomatic men. G. E. Hanks, et al., In: Cancer: Principles and Practice of Oncology, Vol. 1, Fourth Edition, pp. 1073-1113, Philadelphia, Pa.: J. B. Lippincott Co. (1993.). PSA normally is secreted by the prostate at high levels into the seminal fluid, but is present in very low levels in the blood of men with normal prostates. However, in patients with diseases of the prostate including benign prostatic hyperplasia (BPH) and adenocarcinoma of the prostate, the level of PSA can be markedly elevated in the blood and thus is useful as an indicator of prostate disease. PSA levels, however, do not serve to differentiate between BPH and prostate cancer. Thus, the use of PSA as a marker for prostate cancer is problematic. M. K. Schwartz, et al., In: Cancer: Principles and Practice of Oncology, Vol. 1, Fourth Edition, pp. 531-542, Philadelphia, Pa.: J. B. Lippincott Co. 1993. New markers which are more specific for prostate cancer would therefore be beneficial in the initial detection of this disease.
A critical step in managing patients with prostate cancer is the presurgical staging of the cancer to provide prognostic value and criteria for designing optimal therapy. Improved procedures for accurately staging prostate cancer prior to surgery are needed. One study demonstrated that current methods of staging prostate cancer prior to surgery were incorrect approximately fifty percent (50%) of the time. F. Labrie, et al., Urology 44 (Symposium Issue): 29-37 (1994). Prostate cancer management also could be improved by utilizing new markers found in an inappropriate body compartment. Such markers could be mRNA or protein markers expressed by cells originating from the primary prostate tumor but residing in blood, bone marrow or lymph nodes and could be sensitive indicators for metastasis to these distal organs. For example, in patients with metastatic prostate cancer, PSA protein has been detected by immunohistochemical techniques in bone marrow, and PSA mRNA has been detected by RT-PCR in cells of blood, lymph nodes and bone marrow. K. Pantel, et al., Onkologie 18: 394-401 (1995).
New markers which could predict the biologic behavior of early prostate cancers would also be of significant value. Early prostate cancers that threaten or will threaten the life of the patient are more clinically important than those that do not or will not be a threat. G. E. Hanks, supra. A need therefore exists for new markers which can differentiate between the clinically important and unimportant prostate cancers. Such markers would allow the clinician to accurately identify and effectively treat early cancers localized to the prostate which could otherwise metastasize and kill the patient. Further, if one could show that such a marker characteristic of aggressive cancer was absent, the patient could be spared expensive and non-beneficial treatment.
It also would be beneficial to find a prostate associated marker which is more sensitive than PSA in detecting recurrence of prostate cancer and which is not affected by androgens. To date, PSA has proven to be the most sensitive marker for detecting recurrent disease. However, in some cases, tumor progression occurs without PSA elevation due to hormonal therapy utilized for treating the cancer. Although the decrease in androgen results in a concomitant decrease in PSA, it does not necessarily reflect a decrease in tumor metastasis. This complication is the result of androgen-stimulated PSA expression. Part of the decline in PSA observed after androgen ablation is due to diminished PSA expression and not to tumor cell death. G. E. Hanks, supra.
It therefore would be advantageous to provide specific methods and reagents for detecting, diagnosing, staging, monitoring, prognosticating, in vivo imaging, preventing or treating, or determining predisposition to diseases and conditions of the prostate, or for indicating possible predisposition to these conditions. Such methods would include assaying a test sample for products of a gene which are overexpressed in prostate diseases and conditions such as cancer. Such methods may also include assaying a test sample for products of a gene alteration associated with prostate disease or condition. Such methods may further include assaying a test sample for products of a gene whose distribution among the various tissues and compartments of the body have been altered by a prostate-associated disease or condition, such as cancer. Useful reagents include polynucleotide(s), or fragment(s) thereof which may be used in diagnostic methods such as reverse transcriptase-polymerase chain reaction (RT-PCR), PCR, or hybridization assays of mRNA extracted from biopsied tissue, blood or other test samples; polypeptides or proteins which are the translation products of such mRNAs; or antibodies directed against these polypeptides or proteins. Drug treatment or gene therapy for diseases or conditions of the prostate can then be based on these identified gene sequences or their expressed proteins and efficacy of any particular therapy can be monitored. Furthermore, it would be advantageous to have available alternative, non-surgical diagnostic methods capable of detecting early stage prostate disease such as cancer.
The transforming growth factor-beta family of peptide growth factors includes five members, termed TGF-xcex21 through TGF-xcex25, respectively, all of which are composed of homodimers of approximately 25 kD. The TGF-xcex2 family belongs to a larger, extended super family of peptide signaling molecules that includes the Muellerlan inhibiting substance [Cate, R. L. et al., Cell, 45:685-698 (1986)], decapentaplegic [Padgett, R. w. et al., Nature, 325:81-84 (1987)], bone morphogenic factors [Wozney, J. M. et al., Science, 242:1528-1534 (1988)], vg1 [Weeks, D. L., and Melton, D. A., Cell, 51:861867 (1987)], activins [Vale, W. et al., Nature, 321:776-779 (1986)], and inhibins [Mason, A. J. et al., Nature, 318:659663 (1985)]. These factors are similar to TGF-xcex2 in overall structure, but share only approximately 25% amino acid identity with the TGF-xcex2 proteins as well as with each other. All of these molecules are thought to play important roles in modulating growth, development and differentiation.
Using a mouse model system, and limited human immunocytochemical data, Thompson et al [J Cell Biochem, 16H: 54-61 (1992)] conjecture a role for TGF-xcex21 in the pathogenesis of prostate cancer. However, there is no suggestion to use TGF-xcex21 or related peptides as the basis for a diagnostic test. Other work postulates that TGF-xcex21 transcription is elevated in benign prostate hyperplasia. See, e.g., Mori et al., in Prostate (UNITED STATES) 1990, 16 (1) p71-80).
Sequences of four new TGF-xcex2 superfamily member proteins have recently been published (see, International Publication No. WO 96/18730; Japanese Kokai Patent No. Hei 7-250688; GenBank entry gI1813326; GenBank entry gI1872553; and GenBank entry gI2290972). All four protein sequences include 308 amino acid residues with only 9 positions which do not match. It is unclear whether the differences represent polymorphisms or sequencing errors.
This gene is variously described in the above publications as being abundant in the placenta, and therefore playing a role in reproduction, or as a prostate differentiation factor, or as prostate specific, and therefore being useful as a diagnostic to detect benign prostate hyperplasia or prostate cancer. Despite the fact that all of these works are based on essentially the same sequence, there is no unanimity in terms of expression pattern or utility. While Hudson et al. propose the use of this protein for prostate cancer diagnosis, there is no suggestion that this diagnosis can be cancer-specific and that the protein could be used to differentiate from other prostate abnormalities. Indeed, classification of this protein as prostate-specific argues away from a specific diagnostic utility because it suggests the gene is organ-specific and not cancer-specific.
The present invention relates to uses for a prostate cancer-induced growth factor that belongs to the TGF-xcex2 superfamily of proteins. This growth factor is referred to as xe2x80x9cPCIGFxe2x80x9d herein. PCIGF shows preferential induction in prostate cancer. This molecule is structurally and functionally related to TGF-xcex2 and retains seven cysteine residues conserved in the C-terminal, active domain of TGF-xcex2. The polynucleotide sequence for PCIGF is shown in SEQUENCE ID NO 1 and the polypeptide encoded thereby is shown in SEQUENCE ID NO 6. (See, also Japanese Kokai Patent No. Hei 7-250688, to Kato et al.) Surprisingly, the inventors herein have discovered that a peptide sequence encoded by an mRNA which corresponds to a 3xe2x80x2 portion of the above reported 1201 bp sequence is selectively expressed in prostate tumors, but not in the normal prostate, nor in benign prostatic hyperplasia.
Accordingly, the present invention provides a method of distinguishing between prostate cancer and benign prostatic hyperplasia in an individual. In one embodiment, the method comprises contacting a test sample from the individual with at least one PCIGF-specific polynucleotide or complement thereof, wherein said PCIGF-specific polynucleotide has at least 50% identity with a polynucleotide derived from SEQUENCE ID NO 1 or a fragment or complement thereof; and detecting the presence of a target PCIGF polynucleotide in the test sample which binds to said PCIGF-specific polynucleotide. The PCIGF-specific polynucleotide may be attached to a solid phase prior to performing the method.
In another embodiment, the method comprises performing reverse transcription on a test sample from the individual using at least one primer in order to produce cDNA; amplifying the cDNA obtained using PCIGF oligonucleotides as sense and antisense primers to obtain PCIGF amplicon; and detecting the presence of the PCIGF amplicon. The PCIGF oligonucleotides utilized have at least 50% identity with an oligonucleotide derived from SEQUENCE ID NO 1, or a fragment or complement thereof.
In still a further embodiment, the method comprises contacting a test sample from the individual with at least one PCIGF oligonucleotide as a sense primer and with at least one PCIGF oligonucleotide as an anti-sense primer and amplifying to obtain a first stage reaction product; contacting said first stage reaction product with at least one other PCIGF oligonucleotide to obtain a second stage reaction product, with the proviso that the other PCIGF oligonucleotide is located 3xe2x80x2 to the PCIGF oligonucleotides utilized in the first step and is complementary to the first stage reaction product; and detecting the second stage reaction product as an indication of the presence of a target PCIGF polynucleotide. The PCIGF oligonucleotides utilized have at least 50% identity with a sequence derived from SEQUENCE ID NO 1, or a fragment or complement thereof.
The PCIGF polynucleotides in the above embodiments are preferably derived from a sequence of PCIGF from the region spanning nucleotides 629-1201, inclusive, of SEQUENCE ID NO 1, or fragments or complements thereof, or from a region spanning nucleotides 690-956, inclusive, of SEQUENCE ID NO 1, or fragments or complements thereof.
In another embodiment, the method comprises contacting a test sample from the individual suspected of containing PCIGF-specific antibodies with a PCIGF polypeptide. The PCIGF polypeptide contains at least one PCIGF epitope and is derived from an amino acid sequence having at least 50% identity to an amino acid sequence selected from the group consisting of SEQUENCE ID NO 6, SEQUENCE ID NO 7, SEQUENCE ID NO 8 and SEQUENCE ID NO 9 (xe2x80x9cSEQUENCE ID NOS 6-9xe2x80x9d), and fragments thereof. The contacting is performed for a time and under conditions sufficient to allow antigen/antibody complexes to form. The detection of the presence of complexes is an indication of the presence of antibodies specific for a PCIGF antigen. In a preferred embodiment, the method entails the use of a polypeptide having less than the full-length amino acid sequence of PCIGF shown in SEQUENCE ID NO 6 and which comprises an amino acid sequence having at least 50% identity with an amino acid sequence selected from the group consisting of amino acids 220-308 of SEQUENCE ID NO 6 or a fragment thereof, SEQUENCE ID NOS 7-9, and fragments of SEQUENCE ID NOS 7-9.
The present invention also provides a method of detecting a target PCIGF polynucleotide in a test sample which comprises contacting the test sample with at least one PCIGF-specific polynucleotide and detecting the presence of the target PCIGF polynucleotide in the test sample. The PCIGF-specific polynucleotide has at least 50% identity with a polynucleotide derived from the region spanning nucleotides 629-1201, inclusive, of SEQUENCE ID NO 1, or fragments or complements thereof. The PCIGF-specific polynucleotide may be attached to a solid phase prior to performing the method.
The present invention also provides a method for detecting PCIGF mRNA in a test sample, which comprises performing reverse transcription (RT) with at least one primer in order to produce cDNA, amplifying the cDNA so obtained using PCIGF oligonucleotides as sense and antisense primers to obtain PCIGF amplicon, and detecting the presence of the PCIGF amplicon as an indication of the presence of PCIGF mRNA in the test sample. The PCIGF oligonucleotides have at least 50% identity with an oligonucleotide derived from the region spanning nucleotides 629-1201, inclusive, of SEQUENCE ID NO 1, or fragments or complements thereof. Amplification can be performed by the polymerase chain reaction. Also, the test sample can be reacted with a solid phase prior to performing the method, prior to amplification or prior to detection. This reaction can be a direct or an indirect reaction. Further, the detection step can utilize a detectable label capable of generating a measurable signal. The detectable label can be attached to a solid phase.
The present invention further provides a method of detecting a target PCIGF polynucleotide in a test sample suspected of containing target PCIGF polynucleotides, which comprises (a) contacting the test sample with at least one PCIGF oligonucleotide as a sense primer and at least one PCIGF oligonucleotide as an anti-sense primer, and amplifying same to obtain a first stage reaction product; (b) contacting the first stage reaction product with at least one other PCIGF oligonucleotide to obtain a second stage reaction product, with the proviso that the other PCIGF oligonucleotide is located 3xe2x80x2 to the PCIGF oligonucleotides utilized in step (a) and is complementary to the first stage reaction product; and (c) detecting the second stage reaction product as an indication of the presence of a target PCIGF polynucleotide in the test sample. The PCIGF oligonucleotides have at least 50% identity with an oligonucleotide derived from the region spanning nucleotides 629-1201, inclusive, of SEQUENCE ID NO 1, or fragments or complements thereof. Amplification may be performed by the polymerase chain reaction. The test sample can be reacted either directly or indirectly with a solid phase prior to performing the method, or prior to amplification, or prior to detection. The detection step also comprises utilizing a detectable label capable of generating a measurable signal; further, the detectable label can be attached to a solid phase.
Test kits useful for detecting target PCIGF polynucleotide in a test sample are also provided which comprise a container containing at least one PCIGF-specific polynucleotide. The PCIGF-specific polynucleotide has at least 50% identity with a polynucleotide derived from the region spanning nucleotides 629-1201, inclusive, of SEQUENCE ID NO 1, or fragments or complements thereof. These test kits further comprise containers with tools useful for collecting test samples (such as, for example, blood, urine, saliva and stool). Such tools include lancets and absorbent paper or cloth for collecting and stabilizing blood; swabs for collecting and stabilizing saliva; and cups for collecting and stabilizing urine or stool samples. Collection materials such as, papers, cloths, swabs, cups, and the like, may optionally be treated to avoid denaturation or irreversible adsorption of the sample. The collection materials also may be treated with or contain preservatives, stabilizers or antimicrobial agents to help maintain the integrity of the specimens.
The present invention also provides a purified polynucleotide or fragment thereof derived from a PCIGF gene. The purified polynucleotide has at least 50% identity with a polynucleotide derived from the region spanning nucleotides 629-1201, inclusive, of SEQUENCE ID NO 1, or fragments or complements thereof. The purified polynucleotide is capable of selectively hybridizing to the nucleic acid of the PCIGF gene, or a complement thereof. In particular embodiments, the purified polynucleotide has at least 50% identity with a polynucleotide derived from the region spanning nucleotides 690-956, inclusive, of SEQUENCE ID NO 1, or fragments or complements thereof. Further, the purified polynucleotide can be produced by recombinant and/or synthetic techniques. The purified recombinant polynucleotide can be contained within a recombinant vector. The invention further comprises a host cell transfected with the recombinant vector.
The present invention further provides a recombinant expression system comprising a nucleic acid sequence that includes an open reading frame derived from PCIGF. The nucleic acid sequence has at least 50% identity with a nucleic acid sequence derived from the region spanning nucleotides 629-1201, inclusive, of SEQUENCE ID NO 1, or fragments or complements thereof. The nucleic acid sequence is operably linked to a control sequence compatible with a desired host. In particular embodiments, the purified polynucleotide has at least 50% identity with a polynucleotide derived from the region spanning nucleotides 690-956, inclusive, of SEQUENCE ID NO 1 (which encodes amino acids 220-308, inclusive of SEQUENCE ID NO 6), or fragments or complements thereof. Also provided is a cell transfected with this recombinant expression system.
The present invention also provides a polypeptide encoded by PCIGF. The polypeptide can be produced by recombinant technology, provided in purified form, or produced by synthetic techniques. The polypeptide has less than the full-length amino acid sequence of PCIGF shown in SEQUENCE ID NO 6 and comprises an amino acid sequence having at least 50% identity with an amino acid sequence selected from the group consisting of amino acids 220-308 of SEQUENCE ID NO 6 or a fragment thereof, SEQUENCE ID NO 7, SEQUENCE ID NO 8, SEQUENCE ID NO 9 (xe2x80x9cSEQUENCE ID NOS 7-9xe2x80x9d), and fragments of SEQUENCE ID NOS 7-9.
Also provided is a specific binding molecule, such as an antibody, which specifically binds to at least one PCIGF epitope. The antibody can be a polyclonal or monoclonal antibody. The epitope is derived from a polypeptide having less than the full-length amino acid sequence of PCIGF shown in SEQUENCE ID NO 6 and comprises an amino acid sequence having at least 50% identity with an amino acid sequence selected from the group consisting of amino acids 220-308 of SEQUENCE ID NO 6 or a fragment thereof, SEQUENCE ID NOS 7-9, and fragments of SEQUENCE ID NOS 7-9.
Assay kits for determining the presence of PCIGF antigen or anti-PCIGF antibody in a test sample are also included. In one embodiment, the assay kits comprise a container containing at least one PCIGF polypeptide. The polypeptide has less than the full-length amino acid sequence of PCIGF shown in SEQUENCE ID NO 6 and comprises an amino acid sequence having at least 50% identity with an amino acid sequence selected from the group consisting of amino acids 220-308 of SEQUENCE ID NO 6 or a fragment thereof, SEQUENCE ID NOS 7-9, and fragments of SEQUENCE ID NOS 7-9. Further, the test kit can comprise a container with tools useful for collecting test samples (such as blood, urine, saliva, and stool). Such tools include lancets and absorbent paper or cloth for collecting and stabilizing blood; swabs for collecting and stabilizing saliva; and cups for collecting and stabilizing urine or stool samples. Collection materials such as papers, cloths, swabs, cups, and the like, may optionally be treated to avoid denaturation or irreversible adsorption of the sample. These collection materials also may be treated with or contain preservatives, stabilizers or antimicrobial agents to help maintain the integrity of the specimens. Also, the polypeptide can be attached to a solid phase.
In another embodiment of the invention, specific binding molecules, such as antibodies or fragments thereof against the PCIGF antigen, can be used to detect or for image localizations of the antigen in a patient for the purpose of detecting or diagnosing a disease or condition. Such antibodies can be polyclonal or monoclonal, or made by molecular biology techniques, and can be labeled with a variety of detectable labels, including but not limited to radioisotopes and paramagnetic metals. Furthermore, specific binding molecules such as antibodies or fragments thereof, whether monoclonal, polyclonal, or made by molecular biology techniques, can be used as therapeutic agents for the treatment of diseases characterized by expression of the PCIGF antigen. In the case of therapeutic applications, the antibody may be used without derivitization, or it may be derivitized with a cytotoxic agent such as a radioisotope, enzyme, toxin, drug, prodrug, or the like.
Another assay kit for determining the presence of PCIGF antigen or anti-PCIGF antibody in a test sample comprises a container containing a specific binding molecule, such as an antibody, which specifically binds to a PCIGF antigen which comprises at least one PCIGF epitope. The PCIGF antigen has less than the full-length amino acid sequence of PCIGF shown in SEQUENCE ID NO 6 and comprises an amino acid sequence having at least 50% identity with an amino acid sequence selected from the group consisting of amino acids 220-308 of SEQUENCE ID NO 6 or a fragment thereof, SEQUENCE ID NOS 7-9, and fragments of SEQUENCE ID NOS 7-9. These test kits can further comprise containers with tools useful for collecting test samples (such as blood, urine, saliva, and stool). Such tools include lancets and absorbent paper or cloth for collecting and stabilizing blood; swabs for collecting and stabilizing saliva; cups for collecting and stabilizing urine or stool samples. Collection materials, papers, cloths, swabs, cups and the like, may optionally be treated to avoid denaturation or irreversible adsorption of the sample. These collection materials also may be treated with, or contain, preservatives, stabilizers or antimicrobial agents to help maintain the integrity of the specimens. The antibody can be attached to a solid phase.
A method for producing a polypeptide which contains at least one epitope of PCIGF is provided, which method comprises incubating host cells transfected with an expression vector. This vector comprises a polynucleotide sequence encoding a polypeptide, wherein the polypeptide has less than the full-length amino acid sequence of PCIGF shown in SEQUENCE ID NO 6 and comprises an amino acid sequence having at least 50% identity with an amino acid sequence selected from the group consisting of amino acids 220-308 of SEQUENCE ID NO 6 or a fragment thereof, SEQUENCE ID NOS 7-9, and fragments of SEQUENCE ID NOS 7-9.
A method for detecting PCIGF antigen in a test sample suspected of containing PCIGF antigen also is provided. The method comprises contacting the test sample with a specific binding molecule, such as an antibody or fragment thereof, which specifically binds to at least one epitope of a PCIGF antigen, for a time and under conditions sufficient for the formation of antibody/antigen complexes; and detecting the presence of such complexes containing the antibody as an indication of the presence of PCIGF antigen in the test sample. The antibody can be attached to a solid phase and may be either a monoclonal or polyclonal antibody. Furthermore, the antibody specifically binds to at least one PCIGF antigen which has less than the full-length amino acid sequence of PCIGF shown in SEQUENCE ID NO 6 and comprises an amino acid sequence having at least 50% identity with an amino acid sequence selected from the group consisting of amino acids 220-308 of SEQUENCE ID NO 6 or a fragment thereof, SEQUENCE ID NOS 7-9, and fragments of SEQUENCE ID NOS 7-9.
Another method is provided which detects antibodies which specifically bind to PCIGF antigen in a test sample suspected of containing these antibodies. The method comprises contacting the test sample with a polypeptide which contains at least one PCIGF epitope, wherein the PCIGF epitope comprises an amino acid sequence having at least 50% identity with an amino acid sequence encoded by a PCIGF polynucleotide, or a fragment thereof. Contacting is carried out for a time and under conditions sufficient to allow antigen/antibody complexes to form. The method further entails detecting complexes which contain the polypeptide. The polypeptide can be attached to a solid phase. Further, the polypeptide can be a recombinant protein or a synthetic peptide which has less than the full-length amino acid sequence of PCIGF shown in SEQUENCE ID NO 6 and comprises an amino acid sequence having at least 50% identity with an amino acid sequence selected from the group consisting of amino acids 220-308 of SEQUENCE ID NO 6 or a fragment thereof, SEQUENCE ID NOS 7-9, and fragments of SEQUENCE ID NOS 7-9.
The present invention provides a cell transfected with a PCIGF nucleic acid sequence that encodes at least one epitope of a PCIGF antigen, or fragment thereof.
A method for producing antibodies to PCIGF antigen also is provided, which method comprises administering to an individual an isolated immunogenic polypeptide or fragment thereof, wherein the isolated immunogenic polypeptide comprises at least one PCIGF epitope in an amount sufficient to produce an immune response. The isolated, immunogenic polypeptide has less than the full-length amino acid sequence of PCIGF shown in SEQUENCE ID NO 6 and comprises an amino acid sequence having at least 50% identity with an amino acid sequence selected from the group consisting of amino acids 220-308 of SEQUENCE ID NO 6 or a fragment thereof, SEQUENCE ID NOS 7-9, and fragments of SEQUENCE ID NOS 7-9.
Another method for producing antibodies which specifically bind to PCIGF antigen is disclosed, which method comprises administering to a mammal a plasmid comprising a nucleic acid sequence which encodes at least one PCIGF epitope derived from an amino acid sequence which has less than the full-length amino acid sequence of PCIGF shown in SEQUENCE ID NO 6 and comprises an amino acid sequence having at least 50% identity with an amino acid sequence selected from the group consisting of amino acids 220-308 of SEQUENCE ID NO 6 or a fragment thereof, SEQUENCE ID NOS 7-9, and fragments of SEQUENCE ID NOS 7-9.
Also provided is a composition of matter that comprises a PCIGF polynucleotide of at least about 10-12 nucleotides, and fragments or complements thereof. The PCIGF polynucleotide encodes an amino acid sequence having at least one PCIGF epitope. The PCIGF polynucleotide has at least 50% identity with a polynucleotide derived from the region spanning nucleotides 629-1201, inclusive, of SEQUENCE ID NO 1, and fragments or complements thereof. In particular embodiments, the PCIGF polynucleotide has at least 50% identity with a polynucleotide derived from the region spanning nucleotides 690-956, inclusive, of SEQUENCE ID NO 1, and fragments or complements thereof.
Another composition of matter provided by the present invention comprises a polypeptide with at least one PCIGF epitope of about 8-10 amino acids. The polypeptide has less than the full-length amino acid sequence of PCIGF shown in SEQUENCE ID NO 6 and comprises an amino acid sequence having at least 50% identity with an amino acid sequence selected from the group consisting of amino acids 220-308 of SEQUENCE ID NO 6 or a fragment thereof, SEQUENCE ID NOS 7-9, and fragments of SEQUENCE ID NOS 7-9. Also provided is a gene or fragment thereof coding for a PCIGF polypeptide which has at least 50% identity to a polypeptide encoded by the nucleotide sequence spanning nucleotides 629-1201, inclusive, of SEQUENCE ID NO 1 or nucleotides 629-1201, inclusive, of SEQUENCE ID NO 1.
These and other aspects of the present invention should be apparent to those skilled in the art from the teachings herein.